Using faecal profiling to assess the effects of different management types on diet quality in semi-arid savanna

Abstract

We used faecal profiling to assess diet quality of animals under three different management types in a semi-arid savanna, northwest of Kimberley, Northern Cape, South Africa. The levels of faecal crude protein (FCP) and faecal phosphorus (FP) of freeranging springbok (Antidorcas marsupialis) and blue wildebeest (Connochaetes taurinus) on a game ranch, goats and cattle grazing in a communally-managed area, as well as cattle grazing under commercial management were determined in the wet and dry seasons over a period of two years. Plant and soil analyses were also conducted. Goats had the highest FCP and FP of all species in all seasons during the study. It appeared that selective feeders (goats and springbok) and short-grass feeders (wildebeest) do not suffer from low forage quality because their FCP and FP levels were above critical values during all seasons. Contrastingly, cattle need nutrient supplementation because their FCP and FP were below critical nutritional values during the dry seasons. Plant and soil chemical characteristics, especially soil P, had an influence on faecal quality during the study. Clay pans provide an important habitat because of the high soil quality and, consequently, high diet quality. Our surprising finding that faecal CP levels were higher under communal management than under commercial management may be ascribed to higher nutrient deposition (due to higher stocking rates) and greater diet selectivity available to free-ranging animals under communal management. Higher faecal CP and P levels in game animals may also be ascribed to unrestricted movement and, consequently, greater access to palatable plants. The results of this study demonstrate the value of faecal profiling for management of semi-arid savanna livestock and game.

Keywords: diet quality, crude protein, phosphorus, faeces, management types

African Journal of Range & Forage Science 2006, 23(1): 29–38